Marine environments can be very aggressive and present significant challenges in maintaining key infrastructure from the effects of corrosion. In Florida, thousands of bridges are in coastal areas and are continually, or periodically exposed to saltwater conditions. A clear majority of these bridges were constructed using steel reinforced concrete and are supported by precast pilings situated in saltwater, so for this reason, cathodic protection is a necessary strategy for controlling the effects of saltwater induced corrosion.
Toward the early 1980s, the Florida Department of Transportation (FDOT) began the evaluation of different approaches to control saltwater induced corrosion. Some of these included the use of integral pile jackets, specialty materials for concrete repairs, surface applied coatings and other innovative approaches utilizing galvanic anode technology. One such system was jointly developed with industry partners and sponsored by the Federal Highway Administration (FHWA) using integral pile jackets lined with expanded zinc mesh anodes to apply cathodic protection. This innovative approach provides for the problem of concrete repair while at the same time stopping the on-going process of corrosion both combined in one application. Both laboratory and field trials validated the benefits to this approach and confirmed that the system can mitigate corrosion and extend the useful service life of pilings by more than 20 years.
Impressed current cathodic protection (ICCP) is one corrosion management approach adopted by the Port of Newcastle (PoN) for their reinforced concrete wharves. The Port’s West Basin 3 wharf, has ICCP systems installed to select substructure concrete elements (beams). The West Basin 3 ICCP system to the front beam soffit section was installed in 1998 (rear beam soffit sections having been protected from 2014). Other ICCP systems have also been installed by the PoN during the period 2002 to 2005 for the West Basin Wharf 4, East Basin (1 & 2) wharves and the Kooragang K2 wharf. This paper provides background to the different ICCP systems utilized and details performance results for the West Basin 3 front beam ICCP system dating back more than 20 years. Monitoring results are presented and discussed. Performance assessment to protection criteria is undertaken and the CP system maintenance requirements are summarized.
The purpose of this technical committee report is to provide specifiers, designers, and corrosion control personnel information to control the corrosion of conventional reinforcing steel in hydraulic cement concrete using corrosion inhibiting admixtures.
This report describes several types of materials used as corrosion inhibiting admixtures, their selection and evaluation, their proportioning into freshly mixed concrete, and their effects on fresh and hardening/hardened concrete. Corrosion inhibiting admixtures may help delay corrosion initiation and extend the interval of corrosion propagation.
CP coupons have been used since the 1930s by several of the pioneers of the corrosion-control industry, both in North America and in Europe. Over the last two decades, the use of CP coupons has been rediscovered as a practical method to determine the level of polarization of a buried structure and to confirm the voltage drop in a potential measurement. Acceptance of CP coupon technology is slowly occurring. Research sponsored by the pipeline industry has explored the use of CP coupons and has helped validate the use of this technology.